"Yes, he has," the first lady told reporters at the White House when asked whether her husband had finally done what millions of Americans can't seem to do and quit smoking. "It's been almost a year."
She said she didn't know exactly when he quit "because he never smoked a lot" and she never saw him light up.
The issue of Obama's smoking last surfaced in December, when press secretary Robert Gibbs was asked about it and said he hadn't seen Obama smoke in nine months. That would have put Obama's final puffs somewhere in March.
At the time, Gibbs stopped short of asserting that the president had quit outright. But the president's wife was a bit more direct Tuesday.
"He's always wanted to stop," the first lady said, explaining that daughters Malia, 12, and Sasha, 9, are getting to an age where he wants to be able to look them in the face and deny it should they decide to ask him whether he smokes.
Mrs. Obama said the process of quitting has been a "personal challenge" for the president who, when questioned about it in June 2009, acknowledged that he often sneaked an occasional puff.
"I constantly struggle with it," Obama said. "Have I fallen off the wagon sometimes? Yes. Am I a daily smoker, a constant smoker? No."
Obama said he didn't smoke in front of his kids or his family, and had declared himself "95 percent cured." But he acknowledged then that there still were times "where I mess up."
"Once you've gone down this path, then it's something you continually struggle with," he said.
Mrs. Obama said Tuesday that she was very proud of her husband, but that she hasn't pressed him for details.
"I haven't really poked and prodded him on this," she said. "When somebody's doing the right thing you don't mess with them."